Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
12-29-2011, 09:09 AM   #1
Inactive Account

Join Date: Oct 2008
Location: USA
Posts: 7
Pentax SMC-M 50mm f1.4 lens barrel wobble

I have an excellent condition Pentax SMC-M version 50mm f1.4. The focus ring and the lens group show some degree of play, feel like wear out focus helical thread. Is this common problem for this lens? It feel like the parts quality is poorly made, I have see this kind of problem in Nikon AI/AIS lens the old Tamaron SP is superior, too

12-29-2011, 10:02 AM   #2
Senior Member
pezmaker's Avatar

Join Date: Jul 2011
Location: Madison, WI
Photos: Gallery | Albums
Posts: 276
I've got an M 50mm 1.7 (I know I know, not the same lens), that is rock solid and is as high of quality feel as any lens I've touched. I doubt you've got a representative example.

Granted, i've only been using D/SLR cameras for 6 months, but LBA has had my hands on enough glass to believe that what you're describing isn't normal for a pentax M series lens.
12-29-2011, 11:03 AM   #3
Just1MoreDave's Avatar

Join Date: Feb 2007
Location: Aurora, CO
Photos: Gallery | Albums
Posts: 5,027
Production for the M50/1.4 stopped in 1984, so the lens is at least 27 years old. It's 5 or 6 generations old.

I haven't ever seen an M series lens that has a worn out focus helix. Some loose screws could cause the problems you've had.
12-29-2011, 11:56 AM   #4
Veteran Member
borno's Avatar

Join Date: Nov 2006
Location: md-usa
Photos: Gallery | Albums
Posts: 2,580
My a50mm f1.4 wobbles a little and it is about 27 years old (we go way back) but it still does a nice job. I can't remember how tight it was when it was new though.

12-29-2011, 02:10 PM   #5
Veteran Member
bossa's Avatar

Join Date: Jul 2011
Location: Adelaide
Posts: 4,546
If the front element group 'wobbles' a little bit it is unlikely to noticeably affect the image quality - I guess it would behave like a mini shift-lens. If the rear assembly was wobbling then that's a different matter as the lens and film/sensor plane would be out of registration. My A50 F/1.4 has a wobbling barrel too and from what I've read on here that's normal for (at least) that particular lens. My 31LTD has a wobbling front element assembly but the rear group is fine. If the image is pin sharp then I wouldn't worry all that much if I were you.
12-29-2011, 02:19 PM   #6
Inactive Account

Join Date: Oct 2008
Location: USA
Posts: 7
Original Poster
My Nikon new or old never have this problem. I think the focus helical thread has tolerance larger than other lens makers
12-29-2011, 02:29 PM   #7
Veteran Member
wlachan's Avatar

Join Date: Sep 2006
Location: Canada
Photos: Albums
Posts: 2,626
It's unlikely the threads are worn. Perhaps the front or rear lens group which can be tightened, is loose. M lenses should be rock solid.
12-29-2011, 10:37 PM   #8
Junior Member
Hamster's Avatar

Join Date: Jul 2009
Posts: 44
If you take out the front name plate ring, you will see 3 JIS screws. I have come across a few Takumars or M lens where the three screws are lose and give the impression that the barrel is wobling.

12-30-2011, 10:22 AM   #9
Inactive Account

Join Date: Oct 2008
Location: USA
Posts: 7
Original Poster
I partially disassembled this lens I believe the wobble is the focus helical parts have play. The lens does not show lots of wear on the outside.

  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
50mm, 50mm f1.4 lens, f1.4, focus, k-mount, lens, pentax, pentax lens, pentax smc-m 50mm, slr lens, smc-m, smc-m 50mm f1.4
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
Pentax-F 35-70mm lens front barrel is loose violini Pentax SLR Lens Discussion 2 08-08-2011 10:42 PM
For Sale - Sold: Pentax DA* SMC F2.8 16-50mm lens A+ (US) jas Sold Items 2 05-21-2010 01:33 PM
For Sale - Sold: [US] SMC Pentax-M 2.8 28mm Lens, SMC Pentax-A 1.7 50mm soundview Sold Items 4 02-15-2010 02:39 PM
Pentax DA* 16-50 lens barrel movement(?) Egg Salad Pentax SLR Lens Discussion 8 02-05-2010 06:48 AM
Does DA70 barrel wobble? selar Pentax SLR Lens Discussion 2 03-12-2008 05:40 AM

All times are GMT -7. The time now is 07:40 PM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]